Side by Side

Coho Salmon Oncorhynchus kisutch

Typical: 20–26 in, 4–8 lb

Key field mark: Coho has a WHITE gum line (the reliable tell) with tail spots on the upper lobe only; Chinook has a black mouth WITH black gums and spots on both tail lobes; steelhead has a fully white mouth and gums.

• Chrome silver with a metallic blue-green back
• Black spots on the back and the UPPER lobe of the tail only
• Dark/gray mouth interior but a WHITE gum line at the tooth bases
• 12-15 anal fin rays
• Broad, only slightly forked tail
• Typically smaller and slimmer than a Chinook

Full Coho Salmon guide — season, gear and rules →

Sockeye Salmon Oncorhynchus nerka

Typical: 22–28 in, 4–8 lb

Key field mark: Spotless body plus numerous long, fine, closely set gill rakers (count them on the first arch — far more than chum's short, sparse rakers) confirm a sockeye.

• No spots on back or tail
• Bright silver body at sea, greenish-blue back; prominent glassy eye
• Many fine, long, closely spaced gill rakers on first arch (about 28-40)
• Spawners turn bright red with a green head

Full Sockeye Salmon guide — season, gear and rules →

When Each Is Running July — current month highlighted

Where Coho Salmon and Sockeye Salmon Overlap

Both run in Alaska — Southcentral & Southeast — that is where telling them apart actually matters.

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